1. Field of the Invention
The present invention relates to logic gates, scan drivers and organic light emitting displays using the same. More particularly, the invention relates to logic gates capable of being realized with PMOS transistors, and scan drivers and organic light emitting displays using such a logic gate.
2. Description of the Related Art
Various types of flat panel displays are being researched and developed. In general, flat panel displays are capable of having a lower weight and/or a lower volume than cathode ray tubes. Flat panel displays include, e.g., liquid crystal displays, field emission displays, plasma display panels, organic light emitting display devices, etc.
In general, organic light emitting display devices display an image using an organic light emitting diode that generates light by recombination of electrons and holes. Such organic light emitting display devices may be advantageous by having relatively rapid response times and low power consumption characteristics.
Organic light emitting displays may include pixels arranged in a matrix-type manner, a data driver for driving data lines connected to the pixels, and a scan driver for driving scan lines connected to the pixels.
The scan driver may select pixels line by line while sequentially supplying a scan signal during every horizontal period. The data driver may supply a data signal to the pixels selected by the scan signal, line by line. Therefore, each of the pixels may display a predetermined image corresponding to the data signal by supplying a predetermined electric current, corresponding to the respective data signal, to an organic light emitting diode.
The scan driver should be mounted on a panel to, e.g., reduce the manufacturing cost of the organic light emitting display, etc. However, it is difficult to mount the scan driver on the panel because the conventional scan driver is composed of PMOS transistors and NMOS transistors. Thus, a number of masks necessary for manufacturing the transistors may more than when the scan driver only includes one type of transistors, i.e., only NMOS or only PMOS. Accordingly, e.g., a scan driver capable of being realized with only PMOS transistors, i.e., no NMOS transistors, so that it may be formed on the panel is desired.